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621.
BACKGROUND: Type 2 diabetes mellitus is a common disease whose complications have great costs, both in quality of life and expense of treatment. Improving glycemic control, as measured by monitoring glycosylated hemoglobin (HbA1c) levels, can reduce the rate of such complications. OBJECTIVES: The aims of this study were to estimate the lifetime costs associated with diabetes-related complications in a theoretical population receiving metformin monotherapy and to predict the health and economic effect of improving glycemic control in this theoretical population by combining metformin with nateglinide. METHODS: A pharmacoeconomic model was developed to simulate the long-term (30 years) complication rates (microvascular and macrovascular) of a cohort of patients with type 2 diabetes mellitus. The model simulated each year of life for each patient in a theoretical cohort of 10,000 patients until diabetes-related complications were present or death occurred. The mean accumulated costs (direct medical costs for acute care and subsequent care for diabetes-related complications), mean survival time, and the frequency of each type of complication were estimated. Both effectiveness and cost data were discounted at 3%. Sensitivity analyses were conducted on key model input parameters. RESULTS: Average costs of treating complications in theoretical patients undergoing metformin monotherapy were estimated at $29,565 per patient. Savings of $2,742 were estimated per patient for all complications--particularly, nephropathy ($1,166) and macrovascular disease ($632)--when nateglinide was added. The cost-effectiveness ratio of adding nateglinide to metformin was estimated at $27,131 per undiscounted life-year gained (95% CI, $23,710-$28,577) or $43,024 (95% CI, $37,285-$45,193) per additional discounted life-year gained. In the sensitivity analyses, decreasing HbA1c level at baseline, HbA1c upward drift, and duration of disease improved survival. CONCLUSIONS: Combination therapy with nateglinide and metformin, compared with metformin alone, was predicted to reduce the frequency of complications and, thus, treatment costs in this theoretical model. The major factor in cost savings was fewer complications due to nephropathy. The increased drug treatment costs were expected to be offset by the long-term savings from reducing complication rates. 相似文献
622.
Gwenyth?O.?LeeView authors OrcID profile Maribel?Paredes Olortegui Gabriela?Salmón-Mulanovich Pablo?Pe?ataro Yori Margaret?KosekEmail author 《BMC international health and human rights》2016,16(1):26
Background
Informal settlements are common throughout the developing world. In Peru, land occupations, commonly “invasions” in Spanish, are a means by which the extremely poor attempt to obtain access to land. Here, we examine difference in child health between two communities in the Peruvian Amazon, one well-established and one newly formed by ‘invasion’, as captured incidentally by a prospective epidemiological cohort study.Methods
Between 2002 and 2006 a study designed to describe the epidemiology of pediatric enteric infections and child growth in a community-based setting enrolled 442 children in Santa Clara de Nanay, a community adjacent to the city of Iquitos, in Loreto, Peru. In early 2003, a land occupation, commonly called an “invasion” in Spanish, was organized by members of the Santa Clara community, and approximately 20 % of participating study families began occupying privately owned agricultural land adjacent to Santa Clara, thus forming the new community of La Union.Results
Parents in families that chose to invade reported less education than parents in families that chose not to. Children in the new community experienced a higher incidence of diarrheal disease and non-specific fevers, although fewer helminth infections, than children who remained in the established community. At the time of the invasion, there were no differences in anthropometric status between the two groups; however children in the new community experienced greater progressive growth faltering over the course of the longitudinal study.Conclusions
Growth faltering in early childhood represents an enduring loss of human potential. Therefore, our data suggests the human cost of land invasion may be disproportionately borne by the youngest individuals. Innovative policy strategies may be needed to protect this vulnerable group.623.
Virginia Leiro Fernández Maribel Botana Rial Cristina Represas Represas Ana González Piñeiro Victor del Campo Pérez Alberto Fernández-Villar 《Archivos de bronconeumologia》2012,48(12):448-452
Transbronchial needle aspiration (TBNA) of pulmonary lesions without endobronchial affectation in combination with transbronchial biopsy (TBB) has been shown to increase diagnostic perfortmance. The objective of this present study was to analyze whether the combination of TBNA with conventional TBB is a cost-effective approach.MethodologyOurs is a prospective study that included patients with lung nodules or masses with no evidence of endobronchial lesions after flexible bronchoscopy in whom both TBNA and TBB were performed. We analyzed the additional diagnostic value, the impact of TBNA on the cost of the diagnosis and the minimum level of sensitivity required in order for TBNA combined with TBB to be considered a cost-effective diagnostic approach.ResultsThirty-six patients were included in the study, 25 of whom were males. TBB reached a histologic diagnosis in 39% of the cases, and its combination with TBNA diagnosed 47%. The mean diameter of the lesions was significantly greater in the positive TBNA cases compared with the negative cases (31 mm vs 23 mm; P=.034). The cost analysis did not show the additional TBNA to be more cost-effective, despite demonstrating greater diagnostic sensitivity. The minimum sensitivity required for TBNA combined with TBB to be considered a cost-effective approach was 88%.ConclusionThe contribution of TBNA to TBB in the diagnosis of lung nodules or masses without associated endobronchial lesions does not seem to justify the additional economic cost. 相似文献
624.
Feliciano Yu MD MSHI MSPH Maribel Salas MD DSc Young‐il Kim PhD Nir Menachemi PhD MPH 《Pharmacoepidemiology and drug safety》2009,18(8):751-755
This study assesses the impact of computerized physician order entry (CPOE) implementation in pediatric hospitals on reported adverse drug events. Using a nested matched case‐control design; we linked CPOE implementation information from the health information management systems society analytics database with reported adverse drug event (ADE) from the national association of children's hospitals and related institutions case mix comparative data program. Differences were examined using univariate and multivariate conditional logistic regression analyses. Patients from CPOE hospitals were more frequently seen in larger hospitals have more co‐morbidities than those from non‐CPOE hospitals. When matched by admitting diagnosis, age, gender and race, ADE cases were associated with more reported co‐morbidities, and were reported less frequently in hospitals with CPOE. Patients from hospitals without CPOE were 42% more likely to experience reportable ADE after adjusting for the presence of co‐morbidities. In conclusion, we found significant beneficial associations between reportable ADE and CPOE adoption in a representative sample of pediatric hospitals. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
625.
Janina Carlson Susana Ochoa Josep Maria Haro Gemma Escartín Maribel Ahuir Alfonso Gutierrez-Zotes Manel Salamero Joaquim Valero Silvia Cañizares Miquel Bernardo Jose Cañete Pedro Gallo 《Comprehensive psychiatry》2009,50(1):76
Objectives
There are few quality-of-life instruments specifically for schizophrenia; thus, the objective of our study is to adapt and validate the Satisfaction with Life Domains Scale (SLDS) by Baker and Intagliata.Method
This is a validation study in which the subjects were evaluated on 2 occasions (24-48 hours). The sample is composed of people with schizophrenia from 18 to 65 years old and who were seen in one of the following centers: Sant Joan de Déu-SSM, Hospital Clínic, Hospital de Mataró and Hospital Pere Mata. The SLDS was administered, along with Positive and Negative Syndrome Scale, the Clinical General Impression for Schizophrenia, Global Assessment of Function, Disability Assessment Scale—short version, Beck Cognitive Insight, and the Strauss and Carpenter Prognostic Scale. The Cronbach α test was carried out, and the intraclass correlation coefficient was used to assess test-retest reliability, along with Pearson correlations for discriminating validity.Results
The intraclass correlation coefficients oscillated between 0.51 and 0.83. The SLDS did correlate with any of the other instruments with the exception of the Positive and Negative Syndrome Scale general subscale and the Strauss and Carpenter prognostic scale.Conclusions
The Spanish version of the SLDS was shown to be valid and reliable and provides a fast and specific measure for schizophrenia. 相似文献626.
Tissue factor (TF) has been found associated with platelets. Mechanisms responsible for TF-platelet interactions and transport are not fully understood. We explored the response of isolated washed platelets to preparations of recombinant (rTF) or placental (pTF) human TF, exposed on lipid microvesicles (MVs). Sequential ultrastructural and immunocytochemical studies revealed trafficking of these TF preparations, being endocytosed by platelets into channels of the open canalicular system (OCS) and accumulating in the cytoplasm and occasionally in alpha-granules. The process of internalization of TF-MVs was accomplished in less than 30 min, being faster for the placental (pTF) than for the recombinant (rTF) preparation. Signs of mild platelet activation with pseudopodia formation were observed at early stages of internalization. Platelets returned to an apparent resting state after 5-10 min. All of these observations paralleled with modifications on patterns of tyrosine phosphorylation for several signaling proteins. Our studies demonstrate that platelets possess mechanisms to capture and incorporate TF-rich vesicles. These processes were accelerated by the presence of other contaminating cellular antigens in the vesicles (pTF). TF carried by platelets could play a potential role in platelet thrombus formation and by extension in the development of ischemic complications. 相似文献
627.
Diaz-Ricart M Palomo M Fuste B Lopez-Vilchez I Carbo C Perez-Pujol S White JG Escolar G 《Thrombosis research》2008,121(6):873-883
Introduction
Platelet activation leads to signal transduction mechanisms, in which phosphotyrosine proteins play a relevant role.Material and methods
Platelet suspensions were independently activated by collagen and thrombin in the absence and in the presence of two tyrosine kinase inhibitors, tyrphostin 47 and genistein. Samples were processed to visualize morphological changes by electron microscopy, to evaluate changes in cytoskeletal assembly, to analyze modifications in the expression of activation dependent antigens, and the procoagulant activity at the surface level by flow cytometry. Additional experiments applying flow conditions were performed to assess the effect of inhibiting tyrosine phosphorylation on primary platelet adhesion and fibrin formation.Results
Inhibition of tyrosine phosphorylation blocked shape change and cytoskeletal assembly induced by collagen, and inhibited, though partially, those effects due to thrombin. Both activating agents induced the expression of the intraplatelet antigens CD62P and CD63 at the surface, although only collagen promoted expression of anionic phospholipids. Both tyrphostin 47 and genistein prevented those effects. The extent of platelet adhesion on both collagen-coated and subendothelial surfaces was significantly diminished by the presence of the tyrosine kinase inhibitors assayed. Fibrin formation was also significantly reduced.Conclusions
Platelet shape change and secretion during platelet activation depends on tyrosine phosphorylation. In addition, primary adhesion of platelets induces signaling through tyrosine kinases to achieve full spreading, and results in the exposure of a procoagulant surface on platelets. 相似文献628.
629.
Freddy Romero Mariela Pérez Maribel Chávez Gustavo Parra Paula Durante 《Basic & clinical pharmacology & toxicology》2009,105(6):416-424
Abstract: In this work, we aimed to study the effect of uric acid on gentamicin‐induced nephrotoxicity. Male Sprague‐Dawley rats were assigned to one of six groups (six rats each) which received intraperitoneal injections for 9 days: (S) saline; (UA) Uric acid alone; (G) Gentamicin alone; (G + UA) Gentamicin + uric acid; (G rec) Gentamicin recovery and (G + UA rec) Gentamicin + uric acid recovery. In (G rec) and (G + UA rec), rats recovered for 7 days after the last injection. Urine and blood samples were taken on day 0 and at the end of every stage. Kidneys were harvested for histological scoring, determination of renal malondialdehyde (MDA), zymography and western blots for matrix metalloprotease (MMP)‐2 and MMP‐9. Uric acid alone did not provoke changes in biochemical and histological parameters when compared to controls. Gentamicin alone increased significantly plasma creatinine and blood urea nitrogen and caused a moderate histological damage. When combined with uric acid, these conditions worsened. MMP‐9 activity and expression was decreased in rats from group G + UA as compared with rats from group G, while activity of MMP‐2 was similarly increased in both groups when compared to controls. The increase in renal MDA induced by gentamicin was not altered when it was combined with uric acid. During the recovery stage, all biochemical parameters returned to normal levels, though a trend for delay of tubular damage recovery was observed in group G + UA rec when compared with group G rec. The results indicate that uric acid worsens gentamicin‐induced nephrotoxicity. The mechanism is likely to implicate down‐regulation of MMP‐9. 相似文献
630.
Rubin MA Wellmann KA Lewis B Overgaauw BJ Littleton JM Barron S 《Pharmacology, biochemistry, and behavior》2009,92(1):44-50
Neonatal ethanol (EtOH) exposure is associated with central nervous system dysfunction and neurotoxicity in rats. Increases in polyamine levels have been implicated as one underlying mechanism for some of EtOH’s effects on the developing brain. In this study we addressed whether the inhibition of polyamine biosynthesis by α-difluoromethylornithine (DFMO) could reduce behavioral deficits induced by early EtOH exposure. Male and female rat pups received ethanol (6 g/kg/day EtOH i.g.), or isocaloric maltose (control) from postnatal days (PND) 1-8. On PND 8, animals were injected with either saline or DFMO (500 mg/kg, s.c.) immediately following the final neonatal treatment. Subjects were tested for isolation-induced ultrasonic vocalizations (USV) on PND 16; spontaneous activity in an open field apparatus on PND 20 and 21; and balance on PND 31. Animals exposed to EtOH neonatally displayed an increased latency to the first USV and reduced frequencies of USV, hyperactivity and preference for the center of the open field and poorer balance relative to controls. DFMO minimized these deficits in latency to the first USV and balance. These data provide further support that polyamines play a role in some of the functional deficits associated with EtOH exposure during early development and that reducing polyamine activity can improve outcome. 相似文献